One of known light source cooling devices is a device that includes a case, a light source located in the case, and a ventilation device. For the light source that generates heat, for example, a high-pressure mercury lamp is used. The light source generates heat when used. Hence, it is cooled by using a ventilation device such as a fan. The light source cooling device is applied to a projection type display device such as a projector.
In the case of cooling the light source by using the fan, air warmed by the light source is blown to a component disposed on the downstream side of the light source in a flowing direction of the air blown from the fan. This increases the temperature of the component. When the air warmed by the light source is blown to an inner surface of the case, the temperature of the case increases. The increased temperature of the case creates a problem in which the user experiences discomfort when touching the case.
In order to solve the problem, JP2004-170541A (hereinafter, Patent Literature 1) discusses a projector that includes a fan to cool a lamp. The lamp and the fan are housed in a case in which an exhaust port is formed. In this projector, wind is blown to the lamp from the fan disposed in the case. This wind is discharged out of the case through the exhaust port.
In order to prevent an increase in the temperature of the case, the projector discussed in Patent Literature 1 includes a partition plate located between an inner surface of the case and the lamp so as to prevent air warmed by the lamp from being directly blown to the inner surface of the case. A passage is formed between the partition plate and the case. The flow of air blown from the fan is branched into a space where the lamp is located and into the passage between the partition plate and the case. In the flowing direction of the air blown from the fan, the space on the downstream side of the lamp is connected to the passage between the partition plate and the case. The air that passed through the space where the lamp is located and the air that passed through the passage between the partition plate and the case are discharged from the case through the same exhaust port.